U.S. Pat. No. 4,166,753 to Emblem et al discloses a method of producing a usefully gellable cohydrolysate from a normally gellable substance and a not normally gellable substance, preferably a hydrous oxide which has an alkoxy group implanted on it. When hydrolysis is carried out under acid conditions, a slurry is formed from hydrolysate and powdered refractory material which may be set by adding an alkaline reagent.
U.S. Pat. No. 4,197,230 to Baney et al discloses that abrasion resistant siloxane resins having a low degree of organic substitution, thereby tending to be brittle, can be made flexible by including some degree of phenyl substitution. Buffered latent condensation catalysts are disclosed, such as amine carboxylates and quaternary ammonium carboxylates.
In "The Processing and Characterization of DCCA Modified Gel-Derived Silica", Mat. Res. Soc. Symp. Proc. Vol. 32 (1984), Wallace et al examine the role of formamide (NH.sub.2 CHO) as a drying control chemical additive to reduce drying stress in tetramethyl orthosilicate (TMS) gel-derived silica.
D. L. Segal discloses in "Sol-Gel Processing: Routes to Oxide Ceramics Using Colloidal Dispersions of Hydrous Oxides and Alkoxide Intermediates", Journal of Non-Crystalline Solids, 63 (1984) 183-191, that spheres may be formed from a hydrous oxide sol dispersed as liquid droplets in an immiscible organic solvent. In external gelation, removal of anion from the sol droplets by passing ammonia gas or adding a long-chain amine to the solvent results in gel formation.